Circumferentially traveling type tire-changing apparatus



Fein. E4, 1950 s. s wATKlNs @A972644 CIRCUMFERENTIALLY TRAVELING TYPE TIRE CHANGING APPARATUS Filed July 19,'1945 v 5 sneetswsneet l w. Feh 14, E950 s. s. wATmNs 2,49 41,644@

CIRCUMFERENTIALLY TRAVELING TYPE TIRE CHANGING APPARATUS Filed July 19 1945 5 Smets-@Am 2 Feb. 14, 1950 s. s.wATKxNS v CIRCUMFERENTIALLY TRAVELING TYPE TIRE CHANGING APPARATUS i 5 sheets-sheet s Filed July 19, 1945 s. s. WATKIN@ 254979544 CIRCUMFERENTIALLY TRAVEL'LNG TYPE TIRE CHANGING APPARATUS Filed July 19, 19.45 5 Sheets-Sheet 4 Feb SL45 1950 A GAMME L 6 co T 7' /4//7 rma/5 @@@f/ns. /LQM/ Fell 14, 1950 s'. s. WATKlNs.

CIRCUMFERENTIALLY TRAVELING TYPE TIRE CHANGING APPARATUS 5 Sheets-Sheet 5 Filed July 19., 1945 Patented Feb. 1.4., 1950 CIRCUMFERENTIALLY TRAVELING TYPE TIRE-CHANGING APPARATUS Samuel Scott Watkins, Miami, Fla.

Application July 19, 1945, Serial No. 605,929

6 Claims. (Cl. IS7-1.24)

This invention relates to an improved apparatus for changing pneumatic tires, i. e., for mounting pneumatic tire casings on their wheels and stripping them from their wheels. It has particular reference to the handling of heavy,

large size casings of the type used Ion the wheels y.

of aircraft, but is not limited to such use.

Heretofore considerable dililculty has been experienced in the handling of large size tire casings, both in mounting and inremoving them. These casings are heavy and unwieldy. After being mounted on a wheel for even a short time the beads of sucha tire tend to adhere to the rim flanges of the wheel and to resist separation therefrom, and even when the rim is of the drop center or other improved type it is difcult to manipulate the beads, which of course are not capable of being stretched, so as to pass the rim flanges in the operation of separating the casing from the wheel or of mounting it on the Wheel.

Many of the large size tire casings which lare now commonly used on heavy motor vehicles and particularly on aircraft can not be handled for mounting or dismounting by hand, aided only by the use of ordinary tire irons and hammers.

Numerous mechanical devices have been proposed to apply force at the required mechanical advantage to such casings to assist in passing the beads thereof over the Wheel flanges, but all of such prior art devices with which I am acquainted are subject tc certain serious objections and disadvantages. Many of them are elaborate and expensive to make and hard to operate; use of some of them is apt to result in injury to the tire; many of them require the labor of two or more men; and none of them is entirely foolproof and dependable in operation.

i The principal objects of the present invention are to provide a device of the character indicated which can be inexpensively and readily made, which is easily operated by one man possessing no special skill and having no particular experience, and which `will quickly and unfallingly apply a tire to or remove it from a wheel of the drop center or other usual type, regardless of size, weight or other considerations.

A preferred embodiment of the invention which has been thoroughly tested in actual practice and found to give satisfactory and reliable service is illustrated on the accompanying drawings and will be described in detail hereinafter.

The invention is capable of being embodied in other and variously modified forms of construction, all within the principles which will be pointed out in the appended claims. i In the accompanying drawings, 1

Figure 1 is a vertical central section through a. preferred embodiment of the invention showing a Wheel and a tire casing mounted in position for assembly or separation;

Fig. 2 is a side elevational view of a type of jack member used with the device;

Fig. 3 is a fragmentary vertical central sectional view taken through the standard or upright which may form part of the device, showing the hoist for elevating and lowering the main shaft;

Fig. 4 is a side elevational view of the adjustable roller mount;

Figs. 5 and 6 are detail views of the key by which the device is converted from manual to power operation;

Fig. 7 is a horizontal cross-sectional view taken `along the line 1-1 of Fig. 1;

Fig. 8 is a side elevation-al view of the bushing and xed part of the extensible arm by which the roller mount of Fig. 4 is adjustably positioned on the main shaft;

Fig. 9 is a side elevational view of a handle for adjusting various parts of the apparatus;

Fig. 10 is a top plan view of the device with the hoisting upright or standard shown in cross section;

Figs. 11 and 12 are perspective views of a beadloosening roller arm;

Figs. 13-16 are diagrammatic views illustrating the sequence of operations by which a tire bead is loosened from the wheel;

Figs. 17-19 are diagrammatic views illustrating the sequence of loperations by which the bead at one side of a tire casing is separated from the wheel;

Figs. 20-23 are diagrammatic views illustrating the sequence of operations by which the bead at the opposite side of the tire is removed from the wheel;

Figs. 24-28 are diagrammatic views illustrating the sequence of operations by which the bead at one side of a tire is mounted on the wheel;

Figs. 29-34 are diagrammatic views illustrating the sequence of operations by which the bead at the opposite side of a tire is mounted on the Wheel;

Fig. 35 is a perspective view of an attachment for use with the machine;

Fig. 36 is an exploded perspective view of an alternative type of adjustable roller mount;

Fig. 37 is a sectional View taken on the line 3l-3'l of Fig. 39;

Fig. 38 is a top plan view of the same parts with the roller arm omitted;

vthe structure.

Fig. 44 is a diagrammatic sectional view showing use of the modified bushing; and

Figs. 45-55 are diagrammatic views, conforming generally to Figs. 24-34, by illustrating the sequence of operations using the roller mount of Figs. 36-41 to mount a tire on a wheel.

Referring to these drawings', arpreterred form of construction includes a bed in the form of flat plate I mounted horizontally on a plurality of short vertical feet 2, here shown as four in number, each of which is `connected byl a hori- Vzontal "leg 'f3' to the'under surface of the plate I.

'The-legs maybe formed o'fpipe sections, asr shown,

which are securely welded to the plate I so as to radiate at equallyr spaced intervals therefrom, and the feet may be made of similar but shorter pipe sections,-connectedto the legs by Ls or Ts land conveniently fianged'and perforated at their bottomsfor bolting to afloor. `In orderto mount -the device a stable position outdoors on the ground, each of the feet may be provided with a top perforation v4throughwhich a stake Il` may be driven into the ground.

AThe centerof the plate I is perforated to receivea vertical main vshaft 5, shown inthe illustrated embodiment as tubular but which might :be formed from solidv rod stock, which is rotatably supported in4 a thrust Ybearing assembly including a housing 6v which is secured tothe ibottom ofthe plate and has -an runder surface .inthe same plane as the bottoms of the feet 2 so that this housing serves as a centralifoot for The. bearing assembly is-best arrangedltomake thas-haft -removabl'e, as. by use `of the construction shown in Fig. 1 where the shaft isset intoa short ytubular shaft 'I- by means of a bayonet slot and pin connection. The shaft :'I is rotatably mounted-in upper and lower bearings 8 and 9 in the housing'. Forl power driving, as .will be 'hereinafter described, the

Ashort tubular shaft .'I may have fixed around it a worm wheel 8 `engaged by a worm 9" which extends radiallyvfrom'the housing to receive a fdrivenfrom any convenient power source. Ifriction inherentin the` worrnvgearings sunicient The to fix the shaft 5 against rotation under any torque applied to; any'of the/tirehandlingparts fcarried by its upper portion, hereinafter :to be described, whilel rotation of the fshort tubular shaft 'I will rotate the shaft 5. The shaft 5 is .readily removed from the shaft 1 by a fractional reverse turnfollowed by axiallifting.

The upper portion of the main. shaft 5.is screwthreaded and provided with alower nut member IU, an intermediate nut member I I and an upper nut member l2, each vhaving a pair of short "radiatingI arms iIll, II" and I2', respectively,

which serve as handles by which the correspond'- Iing nut rnember'may be rotatedso' as to be moved bearing assembly of the type commonly used with some wheels, but it will be evident that the engagement might be directly with the wheel or with an interposed washer.

Between the intermediate and upper nut members II and I2 a sleeve or bushing I5 having a smooth, non-threaded bore is interposed. It willfbe'evifdent that adjustment of the nut members II and I2 will serve 'to position the bushing I5 at any selected height on the shaft 5. A key- Vway I6 (Fig. 7) is formed in the shaft 5, and a key t1 is movable in and out of this keyway from .a pocket I8 through which thumb screws I9,

rotatably mounted in the key as shown in Figs. 5 and 6, extend from the bushing I5, so that the bushing can be locked against rotation on the shaft, or can be freed for rotation on it.

vExtending radially from the bushing I5, conveniently diametrically opposite from the pocket t8, '.is a telescopically extensible arm 2li*y comprising three lparalilel plates, the' two outer of which, :designated 2|', are. welded to the bushing and spaced apart to form a guideway for the rsingle interposedv plate, designated 2 I length of thearm 2 Ulis determined by the setting The of a screw 22 which Iis: j'ournal'ed in a head 23 upstan'ding from the-outer end'. ofthe interposed plate 2.1", which screw isthreaded in a crossbar `M welded across the outered'ges'of the two outer plates 2'I, above `.the interposed plate. Radial :pins `2.5 may befprovid'ed on the. protruding head `2te-fthes'crew'22 toibe engaged'by ashandle 21 '(Fig;'9)1 or vany other Atype of :head andwrench -may be provided/for rotating the screw to adjust fthe length of the arm 210.

The head :2;3 Lof :the interposed :plateZI sup- .portsv a detachable depending-arm-Z on the lower end of which mounted a roller 29', anda jack 30 (tFi-g. 2f) in 4the 'form of a telescopically .arranged screw Aand sleeve having end ttings for engaging .respectively the shaft 5 and the arm :28 :may :be interposed between the. rshaft to receive the handle 42:'I uby which the `bushing YI5 and the farm 20'may bemanually rotated on the shaft5 when-the key IFI .is withdrawn from .the keyway I6 into the pocket I8.

The'bed plate his provided with two or more radialslots 3 infealchI of which isv mounted ashort '.postfillby4 thefinterflt of `a narrow shank, capped lby a bottom nut 13:5, so that the posts 34 can be adjusted'. at selected radial distances from the shaft 5 Atent-into such openings as are usually formedin therwhelel I3 ,todecrease' the amount ofmetal and lighten :the wheel. Thus. the wheel ist held' ,againstl rotation. on `thepl-ate `I Sleeved over each of the legs f3isanl elongated bushing 36. whichgis slidable r'and rotatable von :the leg and has at Lits inner end `a radiatingarm -31 provided witha roller 38 and. has at its outer end asetscrew -3.9,havir1g radiating -pins or 'other vspecial configuration adapted to be engaged by theha-ndle 2li softhat vith-is handle may be used to rotate thesleevesabout thev legs vto swingthe rollers 38 upvor downfandmay be used also to turn the. setscrewsdown i-nto engagement with the ylegsto fix .the :rollers at any adjusted elevation.

YRising from oneof the feet 2 is a Astandard -40 from the top of-'whichazcrossvarm 4I extends to a point over the endA otthezfshaft.. Acable 42. is

hooked to the upper end of the shaft and trained over pulleys 43, 44 mounted on the cross arm and post and has its end fastened to a winding drum or windlass 45 mounted in the post and having a projecting crank handle 46 by which the shaft and the parts carried by it can be elevated from or lowered into the plate I when the bayonet slot and pin connection in the housing B is d isconnected.

A pressure screw 41 is threaded through the standard 4l) and provided with an operating handle 48 and a broad curved shoe 49 at such elevation on the standard that the shoe will engage and exert pressure against a tire casing I4 of any size that may be used on the device.

The roller arm 28 is made readily detachable from the head 23 of the plate 2| by removal of a single bolt 50 which penetrates the central one of three openings in the arm 28 and is threaded into the head 23. The two endmost openings fit over pins 5| which extend from the head 23 to secure the arm 24 against swinging movement when the bolt 50 is turned down tight. The arrangement is such that the arm 28 may be mounted on the head 23 with either of its fiat side faces engaged with the head, so that the roller 29 will project inwardly toward the shaft 5 as shown in full lines in Fig. 1, or outwardly therefrom, as shown in dotted lines.

Bent arms 52 carrying thin wheels 53 (Figs. 11 and 12) are provided for mounting on the head 23 in place of the straight arm 28, for a purpose which will be hereinafter described.

The device constructed and arranged as thus explained is used in the following way:

The operational steps by which a wheel and tire, mounted on the machine as shown in Fig. 1, are assembled and separated, are shown diagrammatically in Figs. 13-34.

Figs. 13-16 illustrate the sequence of steps by which the machine is used to perform the preliminary operation which is sometimes necessary to loosen a tire casing which has become stuck tightly to the rim flanges of any wheel, such as the drop center type of wheel which has been selected to exemplify the use of the machine. The wheel and tire assembly are mounted on the bed plate I in the position shown in Fig. 1, with the rollers 38 all dropped down out of contact with the tire as shown at the right hand side of Fig. 1 and with the posts 34 engaged in openings in the wheel to hold the wheel against rotation on the bed plate. The main shaft 5 is then lowered through the hub of the wheel and locked in the axially fixed tubular shaft 1 by rotation of the two members of the bayonet connection. The lower nut member In is then turned down into enagement with the upper side of the wheel or with an interposed washer or the bearing assembly shown in Fig. 1, so that the wheel is held against upward movement. A roller 53 and its arm 52 are then mounted on the telescoping arm and the latter arm is then lengthened or shortened by turning the screw 22 to bring the roller into position just over the upper bead of the tire, close to the wheel rim. The intermediate nut member I I is next adjusted to lower the bushing I5 and the arm 20 so that the roller 53 engages the tire bead as shown in Fig. 14. Then with the intermediate nut member I I turned down, out of the way on the shaft 5, the upper nut member I2 is turned down by means of the arms I2', to which the handle 21 may be applied to give increased leverage, to press the roller 53 down against the tire bead. This loosens a portion of the bead from the wheel rim, pushing a short segment of the bead down into the drop center of the wheel. Then by means of the handle 21 engaged in the socket 3|, or by means of power applied to the worm 9', the bushing I5 and arm 2|] are rotated relatively to the fixed wheel I3, either with or without rotation of the shaft 5, so that the pressure of the roller 53 becomes applied progressively all the Way around the upper bead of the tire, and the entire bead thus becomes pushed down into the drop center of the wheel. Fig. 15 shows a portion of the bead pushed into the drop center, and Fig. 16 illustrates the whole upper bead so displaced.

If both beads are stuck and require loosening, the wheel may be turned over on the bed I and the operation repeated on the other bead. The result is shown in Fig. 16, where both beads are depressed into the drop center of the wheel.

Figs. 17-19 show the operations by which the uppermost of the two loosened beads is lifted from the wheel. This operation is begun by replacing the roller 53 and its arm 52 by the roller 29 and arm 28, mounted with the roller on the outer side of its arm, as shown in dotted lines in Fig. 1. The roller is rst inserted under a point on the upper bead, down in the drop center of the wheel, which is most easily accomplished by using the pressure member 41, diametrically opposite the arm 2U, to push the adjacent part of the casing well into the drop center and, if desired or thought necessary, by turning up the adjacent lower roller 38 into.. position to support this portion of the casing in the drop center. This brings the diametrically opposite portion of the casing, adjacent to the location of the roller 29, sufficiently far out beyond the wheel and its rim to admit the roller 29, all as shown in Figs. 1 and 1'1. The intermediate nut member II is then turned up on the shaft 5 to elevate the arm 20 and roller 29 and pull the adjacent short segment of the tire bead up beyond the wheel rim. Rotation of the arm 20, either manually on the stationary shaft 5 or with the shaft driven by power applied to the worm 9, results in pulling the whole extent of the upper bead up beyond the wheel rim, through the stages shown in Figs. 17 and 18, nally resulting in the condition shown in Fig. 19. In this rotating operation the jack 30 may be expanded against the arm 28, as shown in Fig. 1, to relieve friction of the arm 28 on the wheel flange and transfer this friction to the engaged areas of the shaft 5 and the jack 30, where it may be reduced by lubrication.

The inner tube is then easily removed and all four of the lower rollers 38 are turned up to the position shown in Fig. 20, so as to support the casing with its lower bead held in contact with the upper rim of the wheel. This adjustment of the rollers 38 is easily made by fitting the handle 21 successively over each of the set screws 39, then swinging the handle up to rotate the bushing 36 until the roller 38 is in the desired raised position, and then rotating the handle about its axis to turn the set screw down into contact with the leg 3 to hold the roller in position.

The separation of the lower bead from the wheel is shown in Figs. 21-23, and is begun by inserting the roller 29 over the lower bead, between it and the upper rim flange of the wheel, as in Fig. 21. The arm 20 is then raised by the nut member II and turned around the wheel through the portion shown in Fig. 22 until the whole of the lower bead passes the upper rim flange of the wheel, as shown in Fig. 23.

It is then a simple matter to remove the casing from the wheel and from the machine, by pulling the shaft up out of the bed i, or by rst disconnecting the cable :i2 from the shaft and slipping the tire casing up over the end of the shaft.

Figs. 24-84 show how a tire casing is applied to a wheel mounted on the machine in the position indicated in Fig. 1.

The casing is rst laid lon top of the wheel, in the manner shown in Fig. 24, and is then pushed a little to one side so that a short segment of the lower bead will lie out beyond the upper flange of the wheel. The arm 28 is Vmounted on the head 23 of the arm 20 with the roller 29 on the inner side of the arm 28, and suitable adjustments of the arm and nut member lf2 are then made to push the roller 29 down beneath the upper flange of the `wheel and 'press the affected segment of the lower bead down into the drop center, as shown in Fig. '25.

Then the arm 20 is lrotated to turn the roller 29 around the bead and in contact with it, so that the whole bead becomes pushed down over the upper iiange of the wheel, through the stages shown in Figs, -27, until the entire bead has been moved into the drop `center of the wheel, with the upper bead resting on the upper side surface of the wheel, as shown in Fig. 28.

The lower rollers 38 may then be turned up to support the lower bead in the upper bead seat of the wheel, as shown in Fig. 29, whereupon the inner tube may be put 'into the'casing.

The upper bead of the casing is then pushed down into the drop center by the operations shown in Figs. 30-3f3. These steps include pressing the roller 2,9 down against a point lon Athe upper bead to push the adjacent segment thereof down past the upper wheel a'nge, Aas shown in Fig. 3l, and then turning the roller around the bead and in contact with it through the position shown in Fig. 32 until the 'whole upper bead 'has been pushed into the drop center, as shown in Fig. 33.

The tube may then be inilated to expand the two beads of the casing into their seats on 'the wheel as shown in Fig. A34.

Sheet 4 of the drawings illustrates certain modications of some of the elements and vcertain accessories which rare 'useful with the machine.

Fig. 35 shows at "59 a 'small conical element which can be set into the axle 'opening of a wheel in order to receive the thrust 'of the `lower nut member I El. This conical element is useful in connection with wheels that `do not have 'antifriction bearings, one of which is illustrated in Fig. 1.

Figs. 36-41 show a modied vtype of rol-ler mount which can be used in place `cf the lconstruction shown in Fig. 4. The modied form includes .a plate BIJ which takes the place of the plate 2l in the extensible arm 20. This plate E0 has at its outer end a head 6I, formed lmuch like the head 23, :but provided with ra vertically extending central channel $2 .open at 'both its ends and having a xed pin 63 projecting -forwardly from its middle. A-n arm -64 takes `the place of the arm 28 and has la roller 65 journaled just above its lower end and is provided with .a series of holes 6E along-its upper portion. These holes selectively receive the Ypin 53 to determine the eective extent to which the roller -65 defpends from plate E0 Aand hence from 'the sleeve or bushing I5 to which it is secured.

A cap 61 Ymay be dropped over the 'head PBI after the arm 64 is mounted on 'the head. This cap is channeled at its rear to fit the sides of the head, and is closed at its top so as to rest on vthe top Aof the side portions of the head and is open at its center to pass the arm 64. Thus the cap lkeeps the arm 64 from becoming accidentally separated 'from the head 6| and plate 60.

The use of the arm 64 with its lower portion projecting below the roller 65, in mounting a tire on a wheel, is shown diagrammatically in Figs. 45-55. It will be observed from these figures, which parallel Figs. 24-34, that the lower projecting end of the arm '64 facilitates accurate placing of the roller 'U5 properly on the tire bead. This is accomplished by inserting the projecting end portion of the arm down inside the bead, which automatically locates the roller in proper position.

A further advantage ofthe roller 65, mounted as shown in Fig. 36, is that its position relative to the arm 54 does not have to be reversed between the operations of mounting and `removing a tire. This will be appreciated by comparing Fig. 48 with Fig. 17. Fig. 48 shows the roller 65 Aprojecting outwardly from its mount and being used to roll a bead down into the drop center, in the process of mounting the tire. Fig. 17 shows the roller 2.9 being used to pull fa bead up from the drop center past the wheel flange inthe operation 'of removing 4a tire from the wheel. Since both the rollers project outwardly from their mounting, it will be levident that kthe roller E5, mounted as shown in Fig. '39, can be used for installing and removing tires without reversing its direction.

Figs. e2 and 43 show at l0 a modiied type of bushing 36. In this 'modiiication `the bushing is provided with the arm 3l and roller 38, but it carries also a lengthwise adjustable arm ll, formed of :arm elements l2, 'I3 connected by a pin T4 projecting from lone of the elements and fitting selectively into holes 'l5 formed in the other element. 'The arm assembly carries a roller ltB which is like l,the roller 138. .Its use may be explained as follows:

-It frequently happens, vparticularly in the case of large tire casings, that when .the 'assembly vof casing, tubeand 'wheel is completed, it is found that the casing has rotated `somewhat on the wheel, so that vthe valve stein of the tube is misaligned. This requires a 'corresponding reverse rotation of the 'casing to restore alignment. The mo'died bushing construction 'Which has just been .explained greatly facilitates Vthis rotation, when it is .used 'as shownin Figs. 50-53. In vsuch use, the larms 'Irl of the four bushings 70 are turned up vand adjusted r'for length `so that the four rollers :ld will receive the lower side wall o'f the tire `and Ahold it in the .drop center of the wheel,sin the -pfosition shown in Fig. '51. Then, after the `upper bead is l:forced down into the drop center, between 'the operations lshown in Figs. 52-54, both beads are positioned'in the drop center fand `it is a very simple matter t0 rotate the casing lmanually to achieve accurate alignment `ci the .valve stern. 'Of course, subsequent inflation of the vtube forces the beads outwardly against `the wheel anges and binds them securely in place.

I claim:

il. In =a tire changing apparatus, means `for pulling a tire casing bead from the :rim of a wheel comprisinga support for holding the wheel in fxeil position, `a shaft mounted on the ysupport and having a threaded portion extending axially through the Wheel, an element adapted to be inserted beneath a bead of the casing and to extend outwardly therefrom in an axial direction past the adjacent rim of the wheel, a bushing sleeved on the shaft supporting said element, a nut member threaded on the shaft beneath the bushing and adapted to be turned up on the shaft to slide the bushing along the shaft and cause the element to pull a segment of the casing bead past the rim, and means for revolving the bushing and said element about the axis of the shaft around the rim to pull progressively the entire bead past the rim.

2. In a tire changing apparatus, means for pulling a tire casing bead from the rim of a wheel comprising a support for holding the wheel in fixed position, a shaft mounted on the support and having a threaded portion extending axially through the wheel, an element adapted to be inserted beneath a bead of the casing and to extend outwardly therefrom past the adjacent rim of the wheel, a bushing supporting said element sleeved for axial movement on the shaft, means for selectively fixing the bushing against rotation on the shaft and for freeing it for rotation thereon, a nut member threaded on the shaft beneath the bushing and adapted to be turned up on the shaft to slide the bushing along the shaft and cause the element to pull a segment of the casing bead past the rim, and means for selectively rotating the bushing on the shaft and independently thereof operable when the bushing is freed for rotation thereon and for rotating the shaft and bushing together when the bushing is fixed against rotation on the shaft, whereby the element is revolved about the rim of the wheel to pull progressively the entire bead past the rim.

3. In a tire changing apparatus of the type in which a wheel is mounted in fixed Vposition on a support and a tire manipulating element is revolved around the wheel in contact with a bead of the tire, the combination with said support of a shaft extending axially through the mounted wheel and mounting the element on its extended portion, means movable to lock the element against rotation on the shaft or to free it for rotation on the shaft, a handle for rotating the element on the shaft when the element is free on the shaft, and a connection for applying power to the shaft to rotate it and the element together when the element is locked on the shaft.

4. In apparatus for removing from a drop center wheel a tire which has its beads aligned with the drop center of the wheel, a support for holding the Wheel in fixed horizontal position, a standard mounted at one side of the support, pressure means reacting between the standard and the tire for forcing the beads of the tire into the drop center at said side whereby a bead portion at the diametrically opposite side of the tire will be pushed radially beyond the adjacent edge of the wheel rim, and means at the last named side adapted to be inserted beneath the adjacent bead portion and operable to pull the same beyond the wheel rim.

l5. In a tire changing apparatus for drop center wheels, a support for holding the wheel in fixed horizontal position, a standard mounted at one side of the support, means operated at said side for forcing the side walls of the tire axially of the Wheel so as to bring the beads of said side walls into alignment with the drop center of the Wheel, pressure means mounted at said side of the support reacting between the standard and the tire for forcing said beads into the drop center whereby a bead portion of the diametrically opposite side of the tire will be pushed radially beyond the adjacent edge of the wheel rim, and means at the last named side adapted to be inserted beneath the adjacent bead portion and operable to pull the same beyond the wheel rim.

6. Apparatus for removing a tire from a drop center wheel including a support for holding the wheel in axially xed position comprising a hori zontal bed, a plurality of horizontal legs mounted on the support and each having an arm swingable about it and adapted to be fixed in radially adjusted upstanding position for supporting in alignment with the drop center of the Wheel the bead of one side wall of the tire, means mounted on the support and movable against the other side wall of the tire for forcing said Wall in one direction axially of the Wheel so as to free the bead of said side wall from the adjacent wheel rim and force said bead into alignment with the drop center of the Wheel, and an element movable parallel to the axis of the wheel for insertion under said bead and for pulling the same axially of the Wheel in the opposite direction to remove said bead from the Wheel.

SAMUEL SCO'I'I WA'IKINS.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,316,390 Rischard sept. 16, 1919 1,341,727 Weaver June 1, 1920 1,394,400 Berg Oct. 18, 1921 1,402,471 Beck Jan. 3, 1922 1,451,344 Robinett Apr. 10, 1923 1,564,496 Staugaard Dec. 8, 1925 1,742,590 Freivogel Jan. 7, 1930 1,793,864 Manley Feb. 24, 1931 1,936,817 Allen Nov. 28, 1933 2,034,819 Maulis Mar. 24, 1936 2,401,118 Talley et a1. May 28, 1946 FOREIGN PATENTS Number Country Date 121,296 Great Britain Dec. 5, 1919 395,406 Germany July 1, 1922 765,192 France Mar. 19, 1934 

